PEORIA — Maurice Underwood started and paused, started and paused, then started and paused again, struggling to explain techniques he used to maneuver a miniature remote-controlled underwater vehicle through an obstacle course beneath the water of the pool at Woodruff Career and Technical Center.

Finally, he gave up.

“Actually, I really don’t know how I did it,” said Underwood, a junior at Peoria High School. “I just used common sense and the laws of physics.”

Stops, starts and entanglements were the theme Friday as students in the school’s engineering class tested skills they learned in a three-week session of SeaPerch, a national underwater robotics program in which they built remotely-operated vehicles, or ROVs. In the session’s culminating event, five teams of two to four students each competed to see which could get their ROV through a 16-foot obstacle course fastest. Students from Peoria School District 150’s three high schools attend classes at WCTC.

While one student controlled the remote at one end of the pool, another, the spotter, stood on the side shouting instructions such as go right, left, up or down. If a spotter’s directions were unclear, a ROV could end up tangled in the control cord badly enough to require a diver’s assistance and a two-minute penalty. The diver, Becca Pruse — a teacher with degrees in electrical engineering and secondary education who began teaching the class in January — had to jump in the pool to unsnarl an ROV built by student Justice Kasel.

“That was my fault, I can’t drive unless I’m behind the wheel,” said Kasel’s spotter, Sam Willadsen. Both are juniors at Richwoods High School.

But in a class designed to expose students to basic ship and submarine engineering, mistakes can double as accomplishments.

“They learn from their mistakes and what they did wrong,” said Pruse. “Even if a machine fails, they learn about the process of engineering.”

Kasel and Willadsen ended up with the two best times, both just seconds over two minutes.

Pam Adams can be reached at 686-3245 or padams@pjstar.com. Follow her on Twitter @padamspam.